As we type, a Category 5 Cyclone* is due to hit the north east coast of Australia. Cyclone Yasi is projected to have winds in excess of 295 kph (183 mph). [For reference Hurricane Katrina had wind speeds of about 280 kph (175 mph).] Several hours ago the cyclone was causing storm surges to generate waves measured over 9.5 metres high (or 31 ft), even before it made landfall. The illustration above represents Cyclone Yasi's size, relative to the USA. The Herald Sun also have comparisons to Asia and Europe.

This cyclone is bearing down on the Australian state of Queensland, which is still in the throes of recovering from unprecedented flooding that covered an area said to be equal in size to most of the United Kingdom. A flood that the Australian Federal Treasurer said it is the "biggest natural disaster" in Australian history, with Initial estimates of the damage ranging between $5 billion and $15 billion AUD. Further south, the state of Victoria has been experiencing "one of its worst flood events in its history," with a damage bill estimated at $2 billion AUD. And now comes Cyclone Yasi.The Australian Broadcasting Commission, (ABC), the government's national communicator has a news page up on tropical cyclones, mentioning the last cyclone to threaten this region in 2006, Cyclone Larry, who left a repair bill of $1.5 billion AUD in his wake. The ABC note that Cyclone Yasi will be at least twice the diameter of Larry, with more severe winds. We think of those tens of thousands of people now bunkered down in evacuation centres, or with friends and family, for the next terrifying 12 hours without power, and with the possibly of no home to return to.

This has been a summer that few Australians are likely to forget, not the least of all meteorologists. The Sydney Morning Herald reported that the city of Sydney was experiencing its hottest week on record, with the city centre having six consecutive days above 30°C (86°F) and some western suburbs sweltering through seven days exceeding 35°C (95°F). But these temps were put in the shade by a record spell of hot weather in the country's famous Red Centre, where some areas roasted through temperatures of up to 46 degrees Celsius (114.8°F) throughout a ten day period.

Those areas of the state of Victoria not submerged under water (considered in some regions to be a one-in-two-hundred-year-flood) have recently been subjected to the opposite, the ravages of bushfires.

Western Australian has had a spate of bushfires as well, and South Australia has endured a long hot period, similar to the year when its neighbouring state lost over 170 people to bushfires. Emergency services in Australia have been asked to step up to the plate with a regularity this summer, that is without precedent.

But getting back to Cyclone Yasi. The ABC website asked the question: Is climate change a contributor to that? Their answer:

"Climate change would suggest warmer sea temperatures in some parts of the world and temperatures in the Coral Sea this current summer are the highest since records began in the 1900s, so global warming may be a factor in that.

The warmer the atmosphere the more moisture it can contain, and the more thunderstorms you have the more heat is released into the atmosphere through latent heat release. So it implies that would increase either the intensity or number of tropical cyclones."

This summer may be the harbinger of what human induced climate change could hold, not just for Australia's future, but that of other nations too. More intensive extremes of weather, resulting in loss of life, severe destruction to property, infrastructure and agriculture, not to mention the vastly damaging impact on flora, fauna and ecosystems.

*NB: A tropical cyclone is like a hurricane, but they spin in different directions. A Category 5 Cyclone is the most catastrophic on the scale.UPDATE: The reference to Katrina was provided so our predominately US readers might relate to the scale of what was happening. If we only had an Australian audience, I wouldn't have bothered with the comparison.

But here is a infographic from the ABC illustrating comparisons. Click the image for a large version to pop-up. At no time was the suggestion that Yasi was bigger than Katrina, only projected to be stronger.